Snap-action latch for work holding vise



Sept. 21, 1948. H. G. LUFT 2,449,748

SNAP-ACTION-LATCH FOR WORK HOLDING VISE v Filed Sept. 11, 1944 I 3 Sheets-Sheet l my a. Luff BY 3 His Afio r0 6 Sept. 21, 1948.- u 'r 2,449,748

I SNAP-ACTION LATCH FQR WORKIHOLDING VISE Filed Sept. 11, 1944 $Sheets-Sheet 2 INVENTOR.

Homer 6. Luff His A #Orn e y .Sept. 2-1, 1948. H. e; LUFT SNAP-ACTION LATCH FR WORK HOLDING VISE a Sheefs-Sheet 3 I Filed Sept. 11, 1944 INVENTOR. Homer G. LU f7 G mma. His Afi'o rn ey Patented Sept. 21, 1948 entree stares earns-r orrics SNAR-ACTIGN LATCH FQR WORK- HQLDENG VISE Homer G. Loft, Dearborn, Mich.

Application September 11, 1944, Serial No. 553,647

2' Claims. (01. 81- 25) My invention pertains to improved latching, looking or holding means for. drawing and/or securing relatively movable parts together.

It is an object of my. invention to provide hOld'. ing means which will be of a simple rugged construction, and which will-be reliable and positive in- .its action. l

It is also an obiect of my invention to provide improved holding means comprising latch means having a quick snappy. action to facilitate reposited-operations thereof.

It is a further operation of my invention to provide holding means which will be free and convenient in its. operation and which may be operated quickly to apply firm pressure on parts to be held together.

Further objects and advantages are within the scope. of my invention, such as relate to thear rangement, operation and function of the related elements of the structure, to various details of construction-and to combinations of parts, elements per se, andto'economies of manufacture and numerous other features aswill be apparent from a consideration of the specification in conjunction: with the drawings disclosing specific embodiments of the invention, in which: a

Fig, 1 is a front elevational view showing my improved quick lock. or latch, as applied on a jig for holding work;

Fig 2 is a plan view thereof;

Fig. 3 is a side elevational view of therighthand side, the clamp being shown dotted inlseveral positions; i

4 is a front elevational view, partially diagrammatic, the manual control and latch being shown dotted in several positions;

Fig. 5 is an. enlarged longitudinal sectional view taken on line 55 in Fig. 3 showing the self-setting and quick removable pivot bolt for the clamp armof thejig; and.

Fig. 6 is an enlarged. cross-sectional View on line 66 in Fig. 5.

Referring more specifically to the Figs. '1 through 4 of the drawings, I have illustratively disclosed my improved quick lock or latch as utilized on a jig or fixture for quickly receiving and firmly. holding a tubular work piece l I while it is being drilled. transverselyby a drill l3. The. rigid structure or body of sucha jig: may be conveniently. fabricated from a pair of angle iron. pieces 15 firmly clamped togetherin spaced relation on opposite sides of a hollow square iron 8'! by means of bolts 19. The upturned edges. of the anglev irons iii are provided with notches 2! and 23 of V or any other shape suitable to accommodate work pieces to beheld.

A clamp arm 25 is pivotally disposed-tor clamp.- ing down over the notch-23 to hold the work piece. For this purpose therear end of the clamp arm is suitably apertured to passa pivot pin 2'! therethrough and also through. the upper ends, of a pair o1inks-29 the lower ends of which are pivotally disposed upon the ends of a pin. 31 pass.- ing through the end ot the angle iron l5 to-the rear of the notch 23. The clamp arm 2-5 may be conveniently lifted, or even turned back,.to various positions, as represented dotted in Fig, 3, while changing workpieces. The underside of theclamp arm 25 is also provided with. a notch 33 above the notch 23,. and this notch is prefer ably provided with an inwardly directed. work gripper 35. To guidethe drill- I3? accurately into the work piece, the inner side-of. theclamp arm 25 issuitably recessed to receive a suitably. aper tured insert 31 of hardened steel, which. is replaceably pressed or secured therein in any suitable manner. To receive the. sharp lower end-of. the drill [3, after it has pierced the work ll, I provide a piece 39, of softer iron, or other metal; on the upper end of a; screw 4| which passes through an aperturebetween the square iron l1 and the adjacent angle iron 55, from thebottom of. which it can be adjustably raised or lowered.

For quickly and firmly securing the clamp'arm 25 down upon a work. piece II, a manual it latch control element 43 is provided. The latch control element 43 is a heavy and strongelementand it is rotatively mounted upon a heavy pivot pin 45 on the front end-"of the clamp arm 25. Although the latch control element may be made of various suitable shapes, I preferably make it of a substantially disc shape having an aperture inits central portion for'mounting upon-the pivot pin 45. A handleextension M is preferably integral with the latch control element. 43 and it extends from a suitable sigle for convenient manipulation. v l

A second pivot pin MJ-is provided secured-rigidly into the control element 43 with its axis parallel to and spaced from the axislof-the main support pivot 45 for receiving oneend of a latchlever 5| and supporting it for rotation in a plane parallel tothecontrol dise' ltz The other end of the latchcarries, extending from one side inthe plane. of:

tation of the handle 4'l"c1ockwise draws the clamp: I

arm 25 down on the workdue to the crankaction of the pivot pin 49 displaced from the axis of rotation in the center of pin 45. By having the latch '5I of a proper length with the hook 53 suitably disposed so that all the slack is taken up just as the crank pin 49 moves over or above the main pivot pin 45, the work is secured and held very firmly. To facilitate obtaining and maintaining this Condition with various work pieces, or under conditions of wear, the hook 53 may be provided with a contact screw 51 whereby contact with the lower side of the projection 55 is adjusted as desired and the screw is secured by a lock nut 59. As shown in Fig. 3, to provide for further adjustment or taking up wear, the projection 55 is preferably an extension of a plate 6| replaceably secured by screws 63 and pilot pins 42 on the side of the angle iron I5 which may be cut in to provide a shoulder 65. In this manner plates BI can be removed and replaced in accordance with the required condition of the projection 55. As shown in Fig. 1, projection 55 is so mounted that it clears the arcuate portion 61 of the latch control element 43, but at one end of the are 61 is a projection 69 of greater radius which engages the projection 55 and limits the rotation of handle 41 in the latched or locked position. The latch control element 43 is also provided with another radially extended portion II, at the opposite end of the arc 61, which at times abuts a pin I3 mounted stationary on a plate I5. flange IIsecured to the inner side of clamp arm 25 by rivets I6 which also hold a plate I8 on the outer side. The lower ends of flange TI and 4 vised for insertion through the @angle iron I5 to hold the lower ends of the links 29 from the clamp arm. This releasable pivot pin comprises a tubular shank 95 having a head 91 at one end wherein an enlarged counter-bore 99 houses a compression spring IOII. Slidably disposed in said shank is a stem I03 having a head I05 compressing upon the spring IN. The inner end of the stem I03 is slotted or bifurcated forming a fork to receive a curved finger I'I, pivotally secured therein on a pin I09, as shown in more detail in Fig. 6. The side of the tubular shank 95* is provided with a slot I II opening therethrough, and acting to cam the end of the curved finger outwardly as the spring pushes the head outwardly. To release, smaller head I is pushed into the larger head 91 which draws the finger in. The pivot may then be inserted. After insertion, the head I05 is released and the spring throws the finger out in a latching position to secure the pin in any aperture wherein it has been inserted. The inner end of the tubular shank 95 is threaded a short distance to receive a screw I I3 for closing the end of the passage, and for limiting the inward movement of the stem I03 so that the finger I01 will be retracted into the slot III'but not all the way thereinto, as shown dotted. To

, disassemble, the screw I I3 is removed so that the The plate has a plate 18 project down over the upturned web of the adjacent angle iron IS on opposite sides thereof to guide the clamp arm accurately to a proper lateral position.

A snap action spring I9 has one end secured, as by an anchor plate 8| to the end of a pin 83 on an intermediate portion of the latch 5|. The

other end of the spring I9 is secured up on the stem I03 can be pushed further into the tubular shank for completely retracting the finger I0I into the fork in the end of the stem, as represented. The stem I03 may then be drawn from the shank. The surfaces of the large head 91 may be suitably shaped or knurled to facilitate gripping between two fingers while pushing in the smaller head I05.

Although I have shown my locking or latching means on a work holding jig, in the specific embodiment disclosed, it will be understood that it also may be applied with equal utility and advantage in a great many situations where there are relatively movable members, or a stationary structure and a movable member which are to be firmly, quickly and conveniently secured to- 5I. The other or free end of the lever 85 carries a pin 95 whereupon the upper end of the spring 19 is secured. For protection thereof, suitable enclosure means may be provided to cover the latch and snap action mechanism, as will be understood.

Fig. 4 shows in full line the handle 41 turned up in the unlatched' position, as though a Work piece II had just been inserted. The handle 41 is then turned clockwise toward the position B represented dotted. The spring holds the latch firmly against the stationary pin I3, in unlatched position until the latch 5I and the lever 85 are turned in straight alignment and just slightly beyond. Then the latch snaps against the projection with the hook 53 disposed thereunder, as represented dotted. Continued movement of the handled! in a clockwise direction draws up the hook 53 against the underside of the stationary projection 55 drawing the clamp arm 25 firmly down on the work piece. All the slack is snugly taken up just as the pivot pin 49 passes above the mainpivot 4'5 wherebya slight effort on the handleprovides a great clamping force and the clamp remains securely locked.

Fig. 5 shows the details of the self setting and quick releasable pivot pin 3| which I have degether.

It is apparent that Within the scope of the invention modifications and different arrangements may be made other than herein disclosed and the present disclosure is illustrative merely, the invention comprehending variations thereof.

I claim:

1. Snap action holding means comprising, a stationary structure, a member movably secured to said structure, a latch control disc having a central aperture, a pivot passing into said member through said aperture in the control disc for pivotally securing said disc on a portion of said mem her which is movable toward or away from said structure, a second pivot secured in and extending from said disc in a relation axially spaced from and parallel to the first mentioned pivot, a latch having an apertured end pivotally mounted on said second pivot on said disc, the free end of .s'aid latch having a hook projection extending therefrom in the plane of rotation of the latch, a projection extending from said stationary structure to be engaged by said latch and its hook projection when the member is adjacent the structure, a spring secured at one end to an intermediate portion of said latch, a lever, means pivotally securing one end of said lever to the pivoted end of the latch, means securing the other end of said spring to the free end of said lever, slidable connection means between said disc and said lever for turning the lever relatively to the 5 latch to draw the spring to one side or the other and to snap the latch to one side or the other as the disc and the latch are relatively rotated, and a stop for engaging the latch on the side opposite from the side which engages said stationary a projection for holding the latch and limiting its movement relative to the disc as the latter is rotated on its pivot.

2. Snap action holding means in accordance with claim 1 and further characterized by said disc having a pair of projections extending outwardly from its edge or rim in suitably spaced positions so that one of said projections engages the stop when the disc is in unlatched position and the other projection from the disc engages the projection from the stationary structure when the disc is in the latching position.

HOMER G. LUFI.

REFERENCES CITED The following references are of record in the file of this patent:

Number 20 Number UNITED STATES PATENTS Name Date Clark Aug. 1, 1882 Stirckler July 26, 1898 Eckard Dec. 10, 1901 Rossi Apr. 7, 1908 Jenkins July 131, 1920 Jarecki Sept. 13, 1927 Behner May 281, 1929 Agobian June 10, 1930 Mears Sept. 29, 1931 Butt July 4, 1933 McClure Sept. 25, 1934 Turner et a]. Jan. 22:, 1935 Brewington Apr. 9, 1940 Ply Apr. 9, 1940 Hansen July 8, 1941 FOREIGN PATENTS Country Date Great Britain May 10, 1942 

